Apparatus and a method of manufacturing an article from powder material

ABSTRACT

An apparatus for manufacturing an article from powder material including a first table, a second table rotatably mounted on the first table about a first axis and a third table rotatably mounted on the second table about a second axis. A hollow canister is supported by the third table. A vibrator is arranged to vibrate the canister. A first device is arranged to rotate the second table about the first axis and a second device is arranged to rotate the third table about the second axis. A hopper is arranged to supply powder material into the canister and a valve controls the flow of powder material from the hopper into the canister. A processor is arranged to control the valve, the vibrator, the first device and the second device to control the filling and packing density of the canister.

The present invention relates to an apparatus and a method ofmanufacturing an article form powder material, more particularly to anapparatus and a method of manufacturing an article from powder materialby hot isostatic pressing.

Conventionally powder metal articles are manufactured by filling acanister with powder metal, sealing the filled canister, evacuatinggases from the sealed canister, heating and pressing, e.g. hot isostaticpressing (HIP), the canister to consolidate the powder metal to form apowder metal article and finally removing the canister from the powdermetal article.

Hot isostatic pressing is a processing technique in which high isostaticpressure is applied to a powder material contained in a sealed andevacuated canister at a high temperature to produce a substantially 100%dense article. The industry standard is to manufacture the canistersused in the hot isostatic pressing process from mild steel sheet up toapproximately 3 mm thick. The canister conventionally used comprises aplurality of separate portions which are joined together by weldedjoints to form the completed canister. During the hot isostatic pressingcycle, the canister collapses as a result of the high gas pressures andhigh temperatures applied and results in compaction, or consolidation,of the powder material.

As a consequence of the capability of the hot isostatic pressing processto control size and shape, the canisters are currently designed toproduce articles which are considerably oversize, with generally aminimum oversize of about 5 mm. This is considered to be near net shape.The additional material in the oversized article adds a considerableamount of extra material, and there is the cost of the extra material.The extra material has to be removed, for example by machining, afterthe hot isostatic process to result in the final size and final shape ofthe finished powder metal article and this adds more cost. Theadditional material has to undergo hot isostatic processing andincreases the duration of the hot isostatic processing due to theincreased thermal mass of the additional material.

Currently the powder metal article is produced oversize, as mentionedabove, and it is necessary to remove the excess metal from the powdermetal article by machining such that the finished powder metal articlehas the required final shape and final dimensions.

A problem experienced during the filling of a canister designed toproduce a net shape powder metal article is that there may be regionswithin the canister which have relatively small dimensions through whichthe powder metal has to flow in order completely fill all of thecanister. In this type of canister the powder metal flowing into thecanister may form blockages within the region, or regions, of thecanister which have relatively small dimensions and these blockageschoke, or prevent, the flow of powder metal to other regions of thecanister. This will produce a variation in the packing density of thepowder metal in the canister and will produce a variation in theshrinkage of the powder metal in the powder metal article.

There is a requirement to accurately predict the final shape and/or thefinal size of the powder metal article. The final shape and/or the finalsize of the powder metal article is dependent upon the shrinkage,compaction or consolidation, of the powder metal during the hotisostatic pressing. The shrinkage, compaction or consolidation, isdependent upon the packing density of the powder metal within thecanister, because the powder metal compacts in the canister to fill anyvoids within the canister. A consequence of uneven packing density ofthe powder metal within a canister is that there is uneven shrinkagewithin the powder metal article. A further consequence of uneven packingdensity of the powder metal within a canister is that one powder metalarticle may have the powder metal packed to a different density thananother powder metal article and hence the process does not producepowder metal articles with consistent density. Another consequence ofuneven packing density of the powder metal within a canister is that onepowder metal article may have the powder metal packed to a particulardensity at a particular region and another powder metal article may havethe powder metal packed to a different density at the particular regionand hence the process does not produce powder metal articles withconsistent density at particular regions.

There is a need to uniformly fill canisters such that the packingdensity of powder metal in each canister and that the packing density ofthe powder metal at all regions in the canister is the same or thatthere is a minimum variation in packing density throughout the canister.If there is a variation in the packing density of the powder metal in acanister there is a need for the variation in the packing density of thepowder metal in the canister to be the same for all canisters producinga particular powder metal article such that the powder metal articlesare produced consistently the same.

A solution to the problem is to revert to the production of an oversizepowder metal article and to machine to the required shape anddimensions.

It is known from U.S. Pat. No. 5,849,244 to provide a canister on atable which is vibrated during the filling of the canister to improvethe packing density of the powder metal in the canister. U.S. Pat. No.5,849,244 also discloses the use of weighing scale to measure the weightof powder metal remaining in a hopper and hence the weight of powdermetal supplied from the hopper into the canister.

The present invention seeks to provide an apparatus for manufacturing apowder metal article which reduces, preferably overcomes, the abovementioned problems.

Accordingly the present invention provides an apparatus formanufacturing an article from powder material comprising a first table,a second table rotatably mounted on the first table about a first axis,a third table rotatably mounted on the second table about a second axis,a hollow canister supported by the third table, a vibrator arranged tovibrate the canister, a first device to rotate the second table aboutthe first axis, a second device to rotate the third table about thesecond axis, a hopper arranged to supply powder material into thecanister, a valve to control the flow of powder material from the hopperinto the canister and a processor to control the valve, the vibrator,the first device and the second device to control the filling of thecanister.

Preferably the second table is rotatably mounted about a vertical axisand the third table is rotatably mounted about a horizontal axis or thesecond table is rotatably mounted about a horizontal axis and the thirdtable is rotatably mounted about an axis arranged in a planeperpendicular to the horizontal axis.

The second axis may be arranged in a plane perpendicular to the firstaxis

The apparatus may additionally comprise a device to measure the weightof any powder material in the canister, at least one sensor to measurethe depth of any powder material in the canister, the processor beingarranged to analyse the measured depth of any powder material in thecanister, the processor being arranged to determine if the measureddepth of any powder material in the canister corresponds to the measuredweight of any powder material in the canister and if the processordetermines that the measured depth of powder material in the canister isgreater than the depth of powder material corresponding to the weight ofpowder material in the canister then the processor is arranged tovibrate the canister and/or rotate the second table and/or rotate thethird table to redistribute any powder material in the canister.

The processor may comprise a database containing the density of thepowder material, the volume of the canister, the total depth of thecanister, the cross-sectional area of the volume of the canister atdifferent heights of the canister.

The processor may comprise a database relating the depth of powdermaterial in the canister to the weight of powder material in thecanister.

The processor may be arranged to determine a calculated depth of powdermaterial in the canister from the density of the powder material, thecross-sectional area of the volume of the canister at different heightsand the measured weight of powder material in the canister.

The processor may be arranged to compare the calculated depth of powdermaterial in the canister with the measured depth of powder material inthe canister and if the measured depth of powder material in thecanister differs from the calculated depth of powder material by morethan a predetermined amount the processor is arranged to vibrate thecanister and/or rotate the second table and/or rotate the third table.

The processor may comprise a database of the behaviour of differentpowder materials. The database may contain flow characteristics ofdifferent powder materials, size distribution of the particles of thedifferent powder materials. The database may contain information on theflow characteristics of the different powder materials with differentsurface finishes of the canister. The processor may compare informationpertaining to the particular batch of powder material with theinformation in the database. The processor may compare informationpertaining to the surface finish of the canister with the information inthe database.

There may be at least one first sensor arranged at an end of thecanister to measure the depth of any powder material in the canister.There may be at least one second sensor arranged to measure the depth ofany powder material in the canister at a particular region of thecanister. There may be at least one third sensor arranged to move up anddown and around the canister to measure the depth of any powder materialin the canister.

The at least one sensor may comprise an ultrasonic sensor, an X-raysensor or an optical sensor.

The present invention seeks to provide a method of manufacturing apowder metal article which reduces, preferably overcomes, the abovementioned problems.

The present invention also provides a method of manufacturing an articlefrom powder material comprising forming a hollow canister, supplyingpowder material into the hollow canister, vibrating the canister and/orrotating the canister about a first axis and/or rotating the canisterabout a second axis while the powder material is supplied into thecanister, and controlling the flow of powder material into the canister,the vibrating of the canister, the rotating of the canister about thefirst axis and the rotating of the canister about the second axis tocontrol the filling of the canister.

The second axis may be arranged in a plane perpendicular to the firstaxis.

The method may comprise rotating the canister about a vertical axis androtating the canister about a horizontal axis.

The method may additionally comprise measuring the weight of any powdermaterial in the canister, measuring the depth of any powder material inthe canister, analysing the measured depth of any powder material in thecanister, determining if the measured depth of any powder material inthe canister corresponds to the measured weight of any powder materialin the canister and vibrating the canister and/or rotating the canisterabout the first axis and/or rotating the canister about the second axisif the measured depth of powder material in the canister is greater thanthe depth of powder material corresponding to the weight of powdermaterial in the canister to redistribute any powder material in thecanister.

The method may comprise providing a database containing the density ofthe powder material, the volume of the canister, the total depth of thecanister, the cross-sectional area of the volume of the canister atdifferent heights of the canister.

The method may comprise providing a database relating the depth ofpowder material in the canister to the weight of powder material in thecanister.

The method may comprise determining a calculated depth of powdermaterial in the canister from the density of the powder material, thecross-sectional area of the volume of the canister at different heightsand the measured weight of powder material in the canister.

The method may comprise comparing the calculated depth of powdermaterial in the canister with the measured depth of powder material inthe canister and vibrating the canister and/or rotating the canisterabout the first axis and/or rotating the canister about the second axisif the measured depth of powder material in the canister differs fromthe calculated depth of powder material by more than a predeterminedamount.

The method may comprise providing a database of the behaviour ofdifferent powder materials. The database may contain flowcharacteristics of different powder materials, size distribution of theparticles of the different powder materials. The database may containinformation on the flow characteristics of the different powdermaterials with different surface finishes of the canister. The methodmay comprise inputting information pertaining to the particular batch ofpowder material into the processor for comparison with the informationin the database.

The method may comprise measuring the geometry of the canister. Themethod may comprise measuring the internal surface of the canister todetermine its surface finish, or surface roughness. The method maycomprise inputting the information pertaining to the surface finish ofthe canister into the processor for comparison with the information inthe database.

The method may comprise arranging at least one first sensor at an end ofthe canister to measure the depth of any powder material in thecanister.

The method may comprise arranging at least one second sensor to measurethe depth of any powder material in the canister at a particular regionof the canister.

The method may comprise providing at least one third sensor, moving theat least one third sensor up and down and around the canister to measurethe depth of any powder material in the canister.

The method may comprise vibrating the canister at a frequency in therange of 10 to 100 Hz. The method may comprise vibrating the canister ata frequency of 10 to 20 Hz.

The method may comprise rotating the canister back and forth about thefirst axis. The method may comprise rotating the canister back and forthabout the first axis through up to 45°. The method may comprise rotatingthe canister back and forth about the first axis through up to 30°. Themethod may comprise rotating the canister back and forth about the firstaxis through up to 10°.

The method may comprise rotating the canister about the second axis backand forth about the second axis. The method may comprise rotating thecanister back and forth about the second axis through up to +/−45°.

The method may comprise forming the canister from a first cylindricalmember having an outer radius and a second cylindrical member having aninner radius, the inner radius being greater than the outer radius toform an annular chamber between the first cylindrical member and thesecond cylindrical member.

The method may comprise forming at least one recess in an inner surfaceof the second cylindrical member and forming at least one recess in anouter surface of the first cylindrical member.

The method may comprise sealing the filled canister, evacuating thesealed canister to remove gases from the sealed canister, heating andpressing the canister to consolidate the powder material in the canisterto form the powder material article and removing the canister from thepowder material article.

The powder material article may be a gas turbine engine component. Thegas turbine engine component may be a fan casing, a compressor casing,combustion chamber casing or a turbine casing.

The powder material may be a powder metal and the powder materialarticle may be a powder metal article. The powder metal may comprise anickel alloy, a titanium alloy or an iron alloy.

The present invention will be more fully described by way of examplewith reference to the accompanying drawings, in which:

FIG. 1 is a partially cut away view of turbofan gas turbine engineshowing a powder metal casing produced by the method according to thepresent invention.

FIG. 2 is an enlarged cross-sectional view through the powder metalcasing shown in FIG. 1.

FIG. 3 is perspective view of an apparatus for manufacturing a powdermetal article according to the present invention.

FIG. 4 is a cross-sectional view through the apparatus shown in FIG. 3.

FIG. 5 is a perspective view of another apparatus for manufacturing apowder metal article according to the present invention.

FIG. 6 is a cross-sectional view of a further apparatus formanufacturing a powder metal article according to the present invention.

FIG. 7 is a cross-sectional view in the direction of arrows Z-Z in FIG.6.

FIG. 8 is a perspective view of an additional apparatus formanufacturing a powder metal article according to the present invention.

FIG. 9 is a cross-sectional view of another apparatus for manufacturinga powder metal article according to the present invention.

A turbofan gas turbine engine 10, as shown in FIG. 1, comprises in flowseries an intake 11, a fan 12, an intermediate pressure compressor 13, ahigh pressure compressor 14, a combustor 15, a high pressure turbine 16,an intermediate pressure turbine 17, a low pressure turbine 18 and anexhaust 19. The high pressure turbine 16 is arranged to drive the highpressure compressor 14 via a first shaft 26. The intermediate pressureturbine 17 is arranged to drive the intermediate pressure compressor 13via a second shaft 28 and the low pressure turbine 18 is arranged todrive the fan 12 via a third shaft 30. In operation air flows into theintake 11 and is compressed by the fan 12. A first portion of the airflows through, and is compressed by, the intermediate pressurecompressor 13 and the high pressure compressor 14 and is supplied to thecombustor 15. Fuel is injected into the combustor 15 and is burnt in theair to produce hot exhaust gases which flow through, and drive, the highpressure turbine 16, the intermediate pressure turbine 17 and the lowpressure turbine 18. The hot exhaust gases leaving the low pressureturbine 18 flow through the exhaust 19 to provide propulsive thrust. Asecond portion of the air bypasses the main engine to provide propulsivethrust.

The fan 12, the intermediate pressure compressor 13, the high pressurecompressor 14, the combustor 15, the high pressure turbine 16, theintermediate pressure turbine 17 and the low pressure turbine 18 areeach enclosed by a respective casing.

A combustor casing 32 is shown more clearly in FIG. 2 and the combustorcasing 32 comprises an annular radially outwardly extending flange 38 atan upstream end 34 of the combustor casing 32 and an annular radiallyoutwardly extending flange 40 at a downstream end 36 of the combustorcasing 32. The flanges 38 and 40 enable the combustor casing 32 to besecured to a casing of the adjacent high pressure compressor 14 and acasing of the high pressure turbine 16. The flanges 38 and 40 haveapertures 39 and 41 respectively for bolts and nuts or other suitablefasteners to be used to secure the adjacent casings together. Thecombustor casing 32 also has a plurality of circumferentially spacedapertures 42, which have associated bosses 43 and threaded blind holes,to allow fuel injectors to be inserted into the combustion chamber 15.

The combustor casing 32 is manufactured by hot isostatic pressing of apowder material, e.g. a powder metal or powder alloy. The powder alloymay be a nickel-base superalloy, for example RR1000.

An apparatus 50, as shown in FIGS. 3 and 4, for manufacturing anarticle, for example the combustor casing 32, from powder materialcomprises a first table 52, a second table 54 rotatably mounted on thefirst table 52 about a first axis X, a third table 56 rotatably mountedon the second table 54 about a second axis Y and the second axis Y isarranged in a plane perpendicular to the first axis X. A hollow canister58 is supported by the third table 56. A vibrator 60 is arranged tovibrate the canister 58. In particular the vibrator 60 is mounted on thefirst table 52 and thus vibrates the first table 52, the second table54, the third table 56 and the hollow canister 58. The vibrator 60 forexample is arranged to vibrate the canister 58 at a frequency of 10 Hzto 100 Hz, more preferably at a frequency of 10 Hz to 20 Hz. A firstdevice 62 is arranged to rotate the second table 54 about the first axisX and a second device 64 is arranged to rotate the third table 56 aboutthe second axis Y. The first device 62 is arranged to rotate the secondtable 54 through angles α₁ of up to 45°. The second device 64 isarranged to rotate the third table 56 through angles α₂ of up to +/−45°.A hopper 66 is arranged to supply powder material 68 into the canister58 and a valve 70 is arranged to control the flow of powder material 68from the hopper 66 through a main supply pipe 72 and one or more feedpipes 73 into the canister 58. A processor 74 is arranged to control thevalve 70, the vibrator 60, the first device 62 and the second device 64to control the filling of the canister 58. Thus the processor 74provides real time CNC, computer numerical control, of the valve 70, thevibrator 60, the first device 62 and the second device 64 to control thefilling of the canister 58. It is to be noted in this example that thesecond axis Y is coaxial with the axis of the hollow canister 58.

The first device 62 is arranged to rotate the second table 54 morepreferably through angles α₁ of up to 30°, typically through angles α₁of up to 10°. If the second table 54 is rotated through angles at thehigher end of this range it may be necessary to have flexible feed pipes73, such as rubber. However, rubber feed pipes 73 suffer from erosiondue to the powder material 68 and the rubber may lead to contaminationof the powder material 68. It is preferred that the second table 54 isrotated through angles at the lower end of this range, up to 10°, suchthat metal feed pipes 73 may be used.

The second table 54 is rotatably mounted about a horizontal axis X. Thesecond table 54 is rotatably mounted on the first table 52 by a pair ofparallel stub shafts 84 at a first end 54A of the second table 54 andthe stub shafts 84 extend in opposite directions from the opposite sidesof the second table 54 at the first end 54A. The stub shafts 84 aremounted in respective bearings 82 mounted on the first table 52. Thefirst device 62 comprises a pair of rams at the second end 54B of thesecond table 54. The rams 62 are mounted on the opposite sides of thesecond table 54 at the second end 54B and are mounted on the first table52. The rams 62 are arranged to lift, or lower, the second end 54B ofthe second table 54. The rams 62 may be hydraulic rams, pneumatic rams,electric rams or other suitable types of rams.

The third table 56 is rotatably mounted about an axis Y arranged in aplane perpendicular to the horizontal axis X. The axis Y may bevertical. The third table 56 is rotatably mounted on the second table 54by a suitable arrangement of bearings 86 and 88. As shown in FIG. 4 afirst bearing 86 is provided coaxially around the axis Y and axiallybetween the second table 54 and the third table 56. A second bearing 88is provided between a shaft 90 extending from the third table 56 to thesecond device 64 and the second table 54. The second device 64 comprisesfor example an electric motor, but other suitable devices may be used.

The apparatus 50 additionally comprises a device 76 to measure theweight W of any powder material 68 in the canister 58, at least onesensor 78A, 78B and 78C to measure the depth D of any powder material 68in the canister 58. The processor 74 is arranged to analyse the measureddepth D of any powder material 68 in the canister 58, the processor 74is arranged to determine if the measured depth D of any powder material68 in the canister 58 corresponds to the measured weight W of any powdermaterial 68 in the canister 58 and if the processor 74 determines thatthe measured depth D of powder material 68 in the canister 58 is greaterthan the depth of powder material 68 corresponding to the weight W ofpowder material 68 in the canister 58 then the processor 74 is arrangedto vibrate the canister 58 and/or rotate the second table 54 and/orrotate the third table 56 to redistribute any powder material 68 in thecanister 58.

The processor 74 may comprise a database 80 containing the density ofthe powder material 68, the volume of the canister 58, the total depthof the canister 58, the cross-sectional area of the volume of thecanister 58 at different heights of the canister 58. The processor 74may comprise a database 80 relating the depth of powder material 68 inthe canister 58 to the weight of powder material 68 in the canister 58.

The processor 74 may be arranged to determine a calculated depth CD ofpowder material 68 in the canister 58 from the density of the powdermaterial 68, the cross-sectional area of the volume of the canister 58at different heights and the measured weight W of powder material 68 inthe canister 58.

The processor 74 may be arranged to compare the calculated depth CD ofpowder material 68 in the canister 58 with the measured depth D ofpowder material 68 in the canister 58 and if the measured depth D ofpowder material 68 in the canister 58 differs from the calculated depthCD of powder material 68 by more than a predetermined amount theprocessor 74 is arranged to vibrate the canister 58 and/or rotate thesecond table 54 and/or rotate the third table 56.

The processor 74 may comprise a database 80 of the behaviour ofdifferent powder materials 68. In particular the database 80 may containflow characteristics of different powder materials 68, size distributionof the particles of the different powder materials 68. The database 80may contain information on the flow characteristics of the differentpowder materials 68 with different surface finishes of the canister 58.In operation information pertaining to the particular batch of powdermaterial 68 is inputted into the processor 74 for comparison with theinformation in the database 80. The geometry of the canister 58 ismeasured and the internal surface of the canister 58 is measured todetermine its surface finish, or surface roughness. In operation theinformation pertaining to the surface finish of the canister 58 isinputted into the processor 74 for comparison with the information inthe database 80. The processor 74 may then take into account theinformation pertaining to the particular batch of powder material 68,e.g. the flow characteristics of the powder material 68 of the powdermaterial 68 with different surface finishes of the canister 58 and thesize distribution of the powder material 68 and the surface finish ofthe internal surface of the canister 58 to determine the frequency ofvibration of the canister 58, the amplitude of vibration of canister 58,the angle of rotation of the canister 58 on the second table 54 aboutthe first axis X and the angle of rotation of the canister 58 on thethird table 56 about the second axis Y.

There may be at least one first sensor 78A arranged at an end of thecanister 58 to measure the depth D of any powder material 68 in thecanister 58. The first sensor 78A may be arranged for example at theupper end 58A of the canister 58 and be arranged to provide a view in alongitudinal, downward, direction into the canister 58. The first sensor78A may be an ultrasonic sensor arranged to measure the time for anultrasonic signal to travel from the first sensor 78A to any powdermaterial 68 in the canister 58 and back to the ultrasonic sensor 78A andhence to determine the depth of any powder material 68 in the canister58. Alternatively other suitable sensors may be used to measure thedepth from the upper end 58A of the canister 58. There may be at leastone second sensor 78B arranged to measure the depth of any powdermaterial 68 in the canister 58 at a particular region of the canister58. The second sensor 78B for example is an ultrasonic sensor, or anX-ray sensor, arranged to view through the canister 58 to determine thatthe powder material 68 has filled the canister 58 fully up to thatparticular position and the density of the powder material 68 isadequate. There may be at least one third sensor 78C arranged to move upand down and around the canister 58 to measure the depth of any powdermaterial 68 in the canister 58. The third sensor 78C for example is anultrasonic sensor, or an X-ray sensor, arranged to view through thecanister 58 to determine that the powder material 68 has filled thecanister 58 fully up to that particular position and the density of thepowder material 68 is adequate. The third sensor 78C may be used tocheck that the whole of the canister 58 is full, or alternatively tocheck to make sure that there are no regions of the canister 58 whichare not filled with powder material 68. Thus, there may be a firstsensor 78A, a second sensor 78B or a third sensor 78C or any two of thefirst sensor 78A, the second sensor 78B and the third sensor 78C or afirst sensor 78A, a second sensor 78B and a third sensor 78C.

The sensors 78A, 78B, 78C may be arranged to provide feedback signals tothe processor 74. The processor 74 is able to adjust the amplitude ofvibration and/or the frequency of vibration of the first table 52,and/or the angular extent of movement of the second table 54, and/or theangular extent of movement of the third table 56 and the processor 74 isable to determine when to adjust the amplitude of vibration and/or thefrequency of vibration of the first table 52, and/or the angular extentof movement of the second table 54, and/or the angular extent ofmovement of the third table 56 to ensure the canister 58 is filled withpowder material 68 to a controlled packing density. The processor 74 isable to adjust the amplitude of vibration and/or the frequency ofvibration of the first table 52, and/or the angular extent of movementof the second table 54, and/or the angular extent of movement of thethird table 56 and the processor 74 is able to determine when to adjustthe amplitude of vibration and/or the frequency of vibration of thefirst table 52, and/or the angular extent of movement of the secondtable 54, and/or the angular extent of movement of the third table 56 tocorrect the level of filling of powder material 68 within the canister58. The processor 74 may provide dwell times periodically to allow thelevel of powder material 68 to settle within the canister 58.

The at least one sensor 78A, 78B, 78C may comprise an ultrasonic sensor,an X-ray sensor or an optical sensor.

The second table 54 is rotatably mounted about a horizontal axis X andthe third table 56 may be rotatably mounted about a vertical Y.Alternatively, the second table 54 may be rotatably mounted about avertical axis X and the third table 56 may be rotatably mounted about ahorizontal axis Y.

The powder material 68 may be supplied from selected ones of the feedpipes 73 when the third table 56 is positioned at different angles.

If one or more of the sensors 78A, 78B or 78C determines that themeasured level of powder material 68 in the canister 58 is too high forthe amount of powder material 68 supplied into the canister 58, or thatthere is a region of the canister 58 which is not filled adequately withpowder material 68 then the processor 74 vibrates the canister 58 and/orrotates the canister 58 about the axis X and/or rotates the canister 58about axis Y so that the unfilled region of the canister 58 is filledwith powder material 68 and/or so that the measured level of powdermaterial 68 in the canister 58 corresponds to the amount of powdermaterial 68 supplied into the canister 58.

The processor 74 may operate any one of the vibrator 60 to vibrate thefirst table 52, the first device 62 to rotate the second table 54 or thesecond device 64 to rotate the third table 56. Alternatively theprocessor 74 may operate any two of the vibrator 60 to vibrate the firsttable 52, the first device 62 to rotate the second table 54 or thesecond device 64 to rotate the third table 56. The processor 74 mayoperate all three of the vibrator 60 to vibrate the first table 52, thefirst device 62 to rotate the second table 54 or the second device 64 torotate the third table 56.

Most powder material, powder metal, consists of spherical particles.However, the nickel base superalloy known as RR1000 consists ofapproximately 90% spherical particles, 8% spherical particles withsmaller particles attached thereto and approximately 2% irregular shapedparticles. RR1000 consists of 18.5 wt % cobalt, 15 wt % chromium, 5 wt %molybdenum, 2 wt % tantalum, 3.6 wt % titanium, 3 wt % aluminium, 0.5 wt% hafnium, 0.06 wt % zirconium, 0.027 wt % carbon, 0.015 wt % boron andthe balance nickel plus incidental impurities.

There are problems with using powder metal RR1000, firstly the tubessupplying the powder metal may become clogged with powder metal andsecondly and more importantly the powder metal does not flow easily fromthe filling sites adjacent to the tubes supplying the powder metal intothe canister. This problem is exacerbated if the canister has a complexshape, for example if the canister has recesses to define flanges and/orbosses etc in the finished article.

In operation a supply of powder material, powder metal, 68 is maintainedin the hopper 66 and the powder material 68 is maintained in an inertatmosphere, e.g. argon, helium or nitrogen, at atmospheric pressurewithin the hopper 66. The inert atmosphere may be any suitable clean anddry gas which does not have any impurities to react with or contaminatethe power metal. The canister 58 is initially rinsed with alcohol toremove moisture, or water, from the canister. The canister 58 is thenheated to remove the alcohol from the canister 58. The canister 58 isthen purged with an inert atmosphere, e.g. argon, helium or nitrogen orany suitable clean and dry gas which does not have any impurities toreact with or contaminate the power metal. The canister 58 is purgedwith the inert atmosphere either during the heating of the canister 58to remove the alcohol or just after the heating of the canister 58 toremove the alcohol. The canister 58 is purged with a flow of inert gasat a flow rate of 18 to 20 litres per minute or a higher flow rate. Thehopper 66 and the canister 58 are then connected together via the pipe72 in a sealed chamber, e.g. a bag, to prevent air entering the canister58 and/or the hopper 66.

During the filling of the canister 58 with powder metal 68 from thehopper 66 the canister 58 is heated to prevent the condensation ofmoisture in the canister 58 and to aid the flow of the powder metal 68within the canister 58 from the point or points of supply of powdermetal 68 into the canister 58. The hopper 66 is positioned at a positionabove the canister 58 so that there is a flow of powder metal 68 fromthe hopper 66 to the canister 58 due to gravity. In addition a pressuredifference is maintained between the hopper 66 and the canister 58 toaid the flow of powder metal 68 into the canister 58 from the hopper 66to assist the gravity feed of powder metal 68 from the hopper 66 to thecanister 58.

During the filling of the canister 58 the canister 58 may be rotatedabout the first axis X, the second axis Y and vibrated as discussedabove to redistribute the powder metal throughout the canister 58 toensure that the powder metal 68 fills the whole of the canister 58. Thisis especially important for a complex shaped canister 58 which includesrecesses etc to define bosses and/or flanges on the finished powdermetal article 32.

In one arrangement in all modes of operation the first axis X ishorizontal. In modes of operation in which the first device 62 and thesecond device 64 have not been actuated the second axis Y is vertical.In some modes of operation in which the first device 62 has beenactuated the second axis Y is not vertical.

After the canister 58 is completely filled with powder metal, a leakcheck is performed by applying a vacuum to the canister 58 anddetermining if any gas leaks into the canister 58 by measuring thepressure within the canister 58 to determine if the pressure riseswithin the canister 58. If the canister 58 passes the leak check thetubes 72 are sealed by crimping and then the tubes 72 are further sealedby welding, e.g. spot welding etc.

The evacuated and sealed canister 58 containing power metal 68 is thenplaced in a HIP vessel and hot isostatically pressed at a hightemperature and high pressure to consolidate the powder metal anddiffusion bond the powder metal particles together to form a powdermetal article 32. The canister 58 is then removed from the powder metalarticle 34 by machining the canister 58 and/or dissolving the canister58 in acid.

Alternatively, the canister 58 may be a multi-part canister 58 which maybe removed from the powder metal article 32.

The powder metal article 32 may be a net shape article which onlyrequires a minor amount of machining to provide apertures 42 throughbosses and/or apertures through flanges 38 and 40 and finish machiningof the bosses and flanges 38 and 40 etc.

Another apparatus 150 for manufacturing an article, for example acombustor casing 32, from powder material is shown in FIG. 5. Theapparatus 150 is similar to that shown in FIGS. 3 and 4 and comprises afirst table 152, a second table 154 rotatably mounted on the first table152 about a first axis T, a third table 156 rotatably mounted on thesecond table 154 about a second axis U and a fourth table 158 rotatablymounted on the third table 156 about a third axis V. The second axis Uis arranged in a plane perpendicular to the first axis T and the thirdaxis V is arranged in a plane perpendicular to the second axis U. Ahollow canister 160 is supported by the fourth table 158. A vibrator 162is arranged to vibrate the canister 160. In particular the vibrator 162is mounted on the first table 152 and thus vibrates the first table 152,the second table 154, the third table 156, the fourth table 158 and thehollow canister 160. The vibrator 162 for example is arranged to vibratethe canister 160 at a frequency of 10 Hz to 100 Hz, more preferably at afrequency of 10 Hz to 20 Hz. A first device 164 is arranged to rotatethe second table 154 about the first axis T, a second device 166 isarranged to rotate the third table 156 about the second axis U and athird device 168 is arranged to rotate the fourth table 158 about thethird axis V. The first device 164 is arranged to rotate the secondtable 154 through angles α₁ of up to 45°. The second device 166 isarranged to rotate the third table 156 through angles α₃ of up to 45°.The third device 168 is arranged to rotate the fourth table 158 throughangles α₂ of up to +/−45°. A hopper 170 is arranged to supply powdermaterial 172 into the canister 160 and a valve 174 is arranged tocontrol the flow of powder material 172 from the hopper 170 through amain supply pipe 176 and one or more feed pipes 178 into the canister160. A processor 180 is arranged to control the valve 174, the vibrator162, the first device 164, the second device 166 and the third device168 to control the filling of the canister 160. Thus the processor 180provides real time CNC, computer numerical control, of the valve 174,the vibrator 162, the first device 164, the second device 166 and thethird device 168 to control the filling of the canister 160. It is to benoted in this example that the third axis V is coaxial with the axis ofthe hollow canister 160.

The first device 164 is arranged to rotate the second table 154 morepreferably through angles α₁ of up to 30°, typically through angles α₁of up to 10°. It is preferred that the second table 154 is rotatedthrough angles at the lower end of this range, up to 10°, such thatmetal feed pipes 178 may be used.

The second table 154 is rotatably mounted about a horizontal axis T. Thesecond table 154 is rotatably mounted on the first table 152 by a pairof parallel stub shafts 184 at a first end 154A of the second table 154and the stub shafts 184 extend in opposite directions from the oppositesides of the second table 154 at the first end 154A. The stub shafts 184are mounted in respective bearings 182 mounted on the first table 152.The first device 164 comprises a pair of rams at the second end 154B ofthe second table 154. The rams 164 are mounted on the opposite sides ofthe second table 154 at the second end 154B and are mounted on the firsttable 152. The rams 164 are arranged to lift, or lower, the second end154B of the second table 154. The rams 164 may be hydraulic rams,pneumatic rams, electric rams or other suitable types of rams.

The third table 156 is rotatably mounted about an axis U and the axis Uis arranged in a plane perpendicular to the axis T. The axis U may behorizontal. The third table 156 is rotatably mounted on the second table154 by a pair of parallel stub shafts 188 at a first end 156A of thethird table 156 and the stub shafts 184 extend in opposite directionsfrom the opposite sides of the third table 156 at the first end 156A.The stub shafts 188 are mounted in respective bearings 186 mounted onthe second table 154. The second device 166 comprises a pair of rams atthe second end 156B of the third table 156. The rams 166 are mounted onthe opposite sides of the third table 156 at the second end 156B and aremounted on the second table 154. The rams 166 are arranged to lift, orlower, the second end 156B of the third table 156. The rams 166 may behydraulic rams, pneumatic rams, electric rams or other suitable types oframs.

The fourth table 158 is rotatably mounted about an axis V arranged in aplane perpendicular to the axis U. The axis V may be vertical. Thefourth table 158 is rotatably mounted on the third table 156 by asuitable arrangement of bearings, not shown, similar to those shown inFIG. 4. The third device 168 comprises for example an electric motor,but other suitable devices may be used. The axis V is arranged in aplane perpendicular to the axis T.

The processor 180 may comprise a database 190 of the behaviour ofdifferent powder materials 172, as described with reference to FIGS. 3and 4. The apparatus 150 additionally comprises a device 192 to measurethe weight W of any powder material 172 in the canister 160, at leastone sensor 192A, 192B and 192C to measure the depth D of any powdermaterial 172 in the canister 160.

The apparatus 150 operates in a manner similar to that describe withreference to FIGS. 3 and 4 but the processor 180 controls the valve 174,the vibrator 162, the first device 164, the second device 166 and thethird device 168 to control the filling of the canister 160.

The processor 150 may operate any one of the vibrator 162 to vibrate thefirst table 152, the first device 164 to rotate the second table 154,the second device 166 to rotate the third table 156 or the third device168 to rotate the fourth table 158. Alternatively the processor 150 mayoperate any two of the vibrator 162 to vibrate the first table 152, thefirst device 164 to rotate the second table 154, the second device 166to rotate the third table 156 or the third device 168 to rotate thefourth table 158. The processor 150 may operate any three of thevibrator 162 to vibrate the first table 152, the first device 164 torotate the second table 154, the second device 166 to rotate the thirdtable 156 or the third device 168 to rotate the fourth table 158. Theprocessor 150 may operate all four of the vibrator 162 to vibrate thefirst table 152, the first device 164 to rotate the second table 154,the second device 166 to rotate the third table 156 and the third device168 to rotate the fourth table 158.

In one arrangement in all modes of operation the first axis T ishorizontal. In modes of operation in which the first device 164 and thesecond device 166 have not been actuated the second axis U is horizontaland the third axis V is vertical. In some modes of operation in whichthe first device 164 has not been actuated and the second device 166 hasbeen actuated the second axis U is horizontal and the third axis V isnot vertical. In some modes of operation in which the first device 164has been actuated and the second device 166 has been actuated the secondaxis U is not horizontal and the third axis V is not vertical.

A further apparatus 250 for manufacturing an article, for example thecombustor casing 32, from powder material is shown in FIGS. 6 and 7. Theapparatus 250 is similar to and operates in a similar manner to thatshown in FIGS. 3 and 4 and comprises a first support 252, a secondsupport 254 rotatably mounted on the first support 252 about a firstaxis Q, a third support 256 rotatably mounted on the second support 254about a second axis R and a fourth support 258 rotatably mounted on thesupport table 256 about a third axis S. The second axis R is arranged ina plane perpendicular to the first axis Q and the third axis S isarranged in a plane perpendicular to the second axis R. A hollowcanister 260 is supported by the fourth support 258 by grabs 259. Thehollow canister 260 is suspended by the supports in this example ratherthan resting on the tables in the previous examples. The apparatus 250is also provided with a vibrator, devices to rotate the supports,sensors to measure the weight, sensors to measure the level of powdermetal in the canister, a hopper for powder metal, pipes to supply thepowder metal into the canister and a processor but these have beenomitted for clarity. The vibrator may be mounted on the first support.It is to be noted in this example that the third axis S is coaxial withthe axis of the hollow canister 260.

An additional apparatus 350 for manufacturing an article, for example acombustor casing 32, from powder material is shown in FIG. 8. Theapparatus 350 comprises a a first table 352, a second table 354 movablymounted on the first table 352 and a third table 356 rotatably mountedon the second table 354. A hollow canister 58 is supported by the thirdtable 356. The second table 354 is movably mounted on the first table352 by a plurality of rams 364, one ram 364 is provide at each corner352A, 352B, 352C, 352D of the first table 352 to support a correspondingcorner 354A, 354B, 354C and 354D on the second table 354. Each ram 364is connected to the corresponding corner of the first table 352 by auniversal joint (not shown) and is connected to the corresponding cornerof the second table 354 by a universal joint (not shown). The thirdtable 356 is rotatably mounted on the second table 354 about an axis Parranged perpendicular to the plane of the second table 354. The rams364 may be operated hydraulically, pneumatically or electrically. Two ofthe rams 364 along a first side, connecting corners 352A and 352B, ofthe first table 352 may be operated to lift the corresponding firstside, connecting corners 354A and 354B, of the second table 354 whilethe other rams 364 remain un-operated and hence produce a rotationaround a horizontal axis M at the second, opposite, side of the secondtable 354. Alternatively, two of the rams 364 along a first side,connecting corners 352A and 352B, of the first table 352 may be operatedto lift the corresponding first side, connecting corners 354A and 354B,of the second table 354 while the other two rams 364 along the secondside, connecting corners 352C and 352D of the first table 352 may beoperated to lower the corresponding second side, connecting corners 354Cand 354D, of the second table 354 and hence produce a rotation around ahorizontal axis between the first and second sides of the second table354. Similarly two of the rams 364 along a third side, connectingcorners 3528 and 352C, of the first table 352 may be operated to liftthe corresponding third side, connecting corners 3548 and 354C, of thesecond table 354 while the other rams 364 remain un-actuated and henceproduce a rotation around a horizontal axis N at the fourth, opposite,side, connecting corners 354A and 354D, of the second table 354, wherethe third and fourth sides of the first table 352 are the sidesperpendicular to the first and second sides of the first table 352. Theram 364 at a corner 352A of the first table 352 may be operated to liftthe corresponding corner 354A of the second table 354, the ram 364 at anopposite corner 352C may be operated to lower the corresponding corner354C of the second table 354 while the rams 364 at the other corners352B and 352D of the first table 352 remain unoperated to providerotation around an axis extending between the corners 354B and 354D ofthe second table 354. Other permutations of operation and unoperation ofthe rams is possible to provide tilting of the second table 354. It isto be noted in this example that the axis P is coaxial with the axis ofthe hollow canister 58. This may operated in a manner similar to that inFIG. 5.

The apparatus 350 is also provided with a vibrator, devices to move thesecond table relative to the first table, a device to rotate the thirdtable, sensors to measure the weight, sensors to measure the level ofpowder metal in the canister, a hopper for powder metal, pipes to supplythe powder metal into the canister and a processor but these have beenomitted for clarity. The vibrator may be mounted on the first table.

Another apparatus 450 for manufacturing an article, for example acombustor casing 32, from powder material is shown in FIG. 9. Theapparatus 450 comprises a six axis CNC, computer numerically controlled,robot arm. The apparatus 450 comprises a first support 452, a secondsupport 454, a third support 456, a fourth support 458, a fifth support460, a sixth support 462 and a seventh support 464. The second support454 is rotatably mounted on the first support 452 about a first axis Gand the third support 456 is rotatably mounted on the second support 454about a second axis H. The fourth support 458 is rotatably mounted onthe third support 256 about a third axis I and the fifth support 460 isrotatably mounted on the fourth support 458 about a fourth axis J. Thesixth support 462 is rotatably mounted on the fifth support 460 about afifth axis K and the seventh support 464 is rotatably mounted on thesixth support 462 about a sixth axis L. The second, third, fourth andfifth axes H, I, J and K are arranged in a plane perpendicular to thefirst axis G and the sixth axis L is arranged in a plane perpendicularto the second, third, fourth and fifth axes H, I, J, and K. In thisapparatus 450 the first axis G is vertical. The second, third, fourthand fifth axes H, I, J and K are parallel to each other and arehorizontal. A hollow canister 58 is supported by the seventh support 464by grabs 466. The hollow canister 58 is suspended by the supports inthis example rather than resting on tables. The apparatus 450 is alsoprovided with a vibrator, devices to rotate the supports, sensors tomeasure the weight, sensors to measure the level of powder metal in thecanister, a hopper for powder metal, pipes to supply the powder metalinto the canister and a processor but these have been omitted forclarity. The vibrator may be mounted on the seventh support. It is to benoted in this example that the sixth axis L is coaxial with the axis ofthe hollow canister 58.

The processor may operate any one of the vibrator and the devices torotate the supports. Alternatively the processor may operate any two ofthe vibrator and the devices to rotate the supports. The processor mayoperate any three of the vibrator and the devices to rotate thesupports. The processor may operate any four of the vibrator and thedevices to rotate the supports. The processor may operate any five ofthe vibrator and the devices to rotate the supports. The processor mayoperate any six of the vibrator and the devices to rotate the supports.The processor may operate all seven of the vibrator and the devices torotate the supports.

In another arrangement, not shown, similar to that shown in FIG. 8 itmay be possible to provide only three rams, rather than four shown inFIG. 8 and to provide the three rams at the corners of first and secondtriangular tables. Alternatively any suitable number of rams may be usedbetween the first and second table to provide rotation about one or moreaxes of rotation.

In the examples previously described the canister has been rotated aboutan axis of symmetry, e.g. the canister has been rotated about an axiswhich is coaxial with the axis of the cylindrical canister. In anotherarrangement, not shown, it may be possible to arrange for rotation ofthe canister about an axis parallel to but not coaxial with the axis ofthe canister. In another arrangement it may be possible to arrange forrotation of the canister about an axis parallel and coaxial with theaxis of the canister as well as for rotation about an axis parallel tobut not coaxial with the axis of the canister.

The pipes may comprise stainless steel or other suitable metal to resisterosion. The internal surfaces of the pipes are smooth to minimisefriction to reduce the possibility of the powder material blocking thepipes. The pipes have large radius bends and may be arranged in ahelical manner to permit movements of the canister and to minimisestresses within the pipes and buckling of the pipes.

The apparatus in each of the embodiments may be mounted on a vibrationisolating arrangement to minimise the transmission of vibrations fromthe apparatus to a building within which the apparatus is enclosed.

The vibrator may be arranged to indirectly, or directly, vibrate thecanister. The vibrator for example may comprise a transduceracoustically coupled directly to the canister or acoustically coupledindirectly to the canister via all the intervening structures, e.g. allthe intervening tables or intervening supports. The vibrator maycomprise a hammer arranged to directly hit, or strike, and vibrate thecanister. There may be a plurality of transducers to directly orindirectly vibrate the canister or a plurality of hammers to directlyvibrate the canister.

Although FIGS. 3 and 4 have arranged for the second table to berotatably mounted on the first table about a horizontal axis and for thethird table to be rotatably mounted on the second table such that thesecond table is a tilting table and the third table is a rotary table itmay be equally possible for the second table to be rotatably mounted onthe first table about a vertical axis and for the third table to berotatably mounted on the second table about a horizontal axis such thatthe second table is a rotary table and the third table is tilting table.Similarly although FIG. 5 has arranged for the second and the thirdtables to be tilting tables and for the fourth table to be a rotarytable it may be equally possible to arrange the second table to be arotary table and for the third and fourth tables to be tilting tables orto arrange third table to be a rotary table and for the first and fourthtables to be tilting tables.

The present invention provides an apparatus, which may be programmable,to enable variation in the filling conditions of the physical parametersinfluencing the flow of the powder material into the canister. Theapparatus enables multi-axis vibrational load to be imparted to thepowder material in the canister for example by rocking the canisterbackwards and forwards around respective rotational axes and byintroducing vibrational oscillations into the walls of the canister. Thepresent invention provides several sensing systems to measure the heightof the powder material in the canister, the packing density of thepowder material in the canister, the weight of the powder material inthe canister and provide feedback. The outputs from the sensing systemsare used to control the process variables, leading to real time processcontrol and adjustment via feedback monitoring. The apparatus may changethe amplitude of any vibrational oscillations, the angle through whichthe canister is rocked, or rotated, for each of the axis of rotation.The apparatus provides two, or more, axes around which the canister maybe rotated or oscillated back and forth.

Although the present invention has been described with reference topowder metal it is equally applicable to the manufacture of a powderceramic article from powder ceramic or the manufacture of a cermetarticle from a combination of powder metal and powder ceramic.

1. A method of manufacturing an article from powder material comprisingforming a hollow canister, supplying powder material into the hollowcanister, vibrating the canister and/or rotating the canister about afirst axis and/or rotating the canister about a second axis while thepowder material is supplied into the canister, and controlling the flowof powder material into the canister, the vibrating of the hollowcanister, the rotating of the canister about the first axis and therotating of the canister about the second axis to control the filling ofthe canister.
 2. A method as claimed in claim 1 comprising rotating thecanister about a vertical axis and rotating the canister about ahorizontal axis.
 3. A method as claimed in claim 1 additionallycomprising measuring the weight of any powder material in the canister,measuring the depth of any powder material in the canister, analysingthe measured depth of any powder material in the canister, determiningif the measured depth of any powder material in the canister correspondsto the measured weight of any powder material in the canister andvibrating the canister and/or rotating the canister about the first axisand/or rotating the canister about the second axis if the measured depthof powder material in the canister is greater than the depth of powdermaterial corresponding to the weight of powder material in the canisterto redistribute any powder material in the canister.
 4. A method asclaimed in claim 3 comprising providing a database containing thedensity of the powder material, the volume of the canister, the totaldepth of the canister, the cross-sectional area of the volume of thecanister at different heights of the canister.
 5. A method as claimed inclaim 3 comprising providing a database relating the depth of powdermaterial in the canister to the weight of powder material in thecanister.
 6. A method as claimed in claim 4 comprising determining acalculated depth of powder material in the canister from the density ofthe powder material, the cross-sectional area of the volume of thecanister at different heights and the measured weight of powder materialin the canister.
 7. A method as claimed in claim 6 comprising comparingthe calculated depth of powder material in the canister with themeasured depth of powder material in the canister and vibrating thecanister and/or rotating the canister about the first axis and/orrotating the canister about the second axis if the measured depth ofpowder material in the canister differs from the calculated depth ofpowder material by more than a predetermined amount.
 8. A method asclaimed in claim 4 comprising providing a database containing flowcharacteristics of different powder materials, size distribution of theparticles of the different powder materials and/or the flowcharacteristics of the different powder materials with different surfacefinishes of the canister.
 9. A method as claimed in claim 3 comprisingarranging at least one first sensor at an end of the canister to measurethe depth of any powder material in the canister.
 10. A method asclaimed in claim 3 comprising arranging at least one second sensor tomeasure the depth of any powder material in the canister at a particularregion of the canister.
 11. A method as claimed in claim 3 comprisingproviding at least one third sensor, moving the at least one thirdsensor up and down and around the canister to measure the depth of anypowder material in the canister.
 12. A method as claimed in claim 1comprising vibrating the canister at a frequency in the range of 10 to100 Hz.
 13. A method as claimed in claim 12 comprising vibrating thecanister at a frequency of 10 to 20 Hz.
 14. A method as claimed in claim1 comprising rotating the canister back and forth about the first axis.15. A method as claimed in claim 14 comprising rotating the canisterback and forth about the first axis through up to 45°.
 16. A method asclaimed in claim 1 comprising rotating the canister back and forth aboutthe second axis.
 17. A method as claimed in claim 16 comprising rotatingthe canister back and forth about the second axis through up to +/−45°.18. A method as claimed in claim 1 comprising forming the canister froma first cylindrical member having an outer radius and a secondcylindrical member having an inner radius, the inner radius beinggreater than the outer radius to form an annular chamber between thefirst cylindrical member and the second cylindrical member.
 19. A methodas claimed in claim 18 comprising forming at least one recess in aninner surface of the second cylindrical member and forming at least onerecess in an outer surface of the first cylindrical member.
 20. A methodas claimed in claim 1 comprising sealing the filled canister, evacuatingthe sealed canister to remove gases from the sealed canister, heatingand pressing the canister to consolidate the powder material in thecanister to form the powder material article and removing the canisterfrom the powder material article.
 21. A method as claimed in claim 1wherein the powder material article is a gas turbine engine component.22. A method as claimed in claim 21 wherein the gas turbine enginecomponent is selected from the group consisting of a fan casing, acompressor casing, a combustion chamber casing and a turbine casing. 23.A method as claimed in claim 1 wherein the powder material is a powdermetal and the powder material article is a powder metal article.
 24. Amethod as claimed in claim 23 wherein the powder metal is selected fromthe group consisting of a nickel alloy, a titanium alloy and an ironalloy.
 25. A method as claimed in claim 1 comprising rotating thecanister about a third axis, and additionally controlling the rotatingof the canister about the third axis to control the filling of thecanister.
 26. A method as claimed in claim 3 comprising measuring thedepth of any powder material in the canister using a sensor selectedfrom the group consisting of an ultrasonic sensor, an X-ray sensor andan optical sensor.
 27. An apparatus for manufacturing an article frompowder material comprising a first table, a second table rotatablymounted on the first table about a first axis, a third table rotatablymounted on the second table about a second axis, a hollow canistersupported by the third table, a vibrator arranged to vibrate thecanister, a first device to rotate the second table about the firstaxis, a second device to rotate the third table about the second axis, ahopper arranged to supply powder material into the canister, a valve tocontrol the flow of powder material from the hopper into the canisterand a processor to control the valve, the vibrator, the first device andthe second device to control the filling of the canister.
 28. Anapparatus as claimed in claim 27 additionally comprising a device tomeasure the weight of any powder material in the canister, at least onesensor to measure the depth of any powder material in the canister, theprocessor being arranged to analyse the measured depth of any powdermaterial in the canister, the processor being arranged to determine ifthe measured depth of any powder material in the canister corresponds tothe measured weight of any powder material in the canister and if theprocessor determines that the measured depth of powder material in thecanister is greater than the depth of powder material corresponding tothe weight of powder material in the canister then the processor isarranged to vibrate the canister and/or rotate the second table and/orrotate the third table to redistribute any powder material in thecanister.
 29. An apparatus for manufacturing an article from powdermaterial comprising a first support, a second support rotatably mountedon the first support about a first axis, a third support rotatablymounted on the second support about a second axis, a hollow canistersupported by the third support, a vibrator arranged to vibrate thecanister, a first device to rotate the second support about the firstaxis, a second device to rotate the third support about the second axis,a hopper arranged to supply powder material into the canister, a valveto control the flow of powder material from the hopper into the canisterand a processor to control the valve, the vibrator, the first device andthe second device to control the filling of the canister.
 30. Anapparatus as claimed in claim 29 additionally comprising a device tomeasure the weight of any powder material in the canister, at least onesensor to measure the depth of any powder material in the canister, theprocessor being arranged to analyse the measured depth of any powdermaterial in the canister, the processor being arranged to determine ifthe measured depth of any powder material in the canister corresponds tothe measured weight of any powder material in the canister and if theprocessor determines that the measured depth of powder material in thecanister is greater than the depth of powder material corresponding tothe weight of powder material in the canister then the processor isarranged to vibrate the canister and/or rotate the second table and/orrotate the third table to redistribute any powder material in thecanister.